use std::path::Path;
fn main() {
    let path = Path::new(".");
    let _display = path.display();
    let new_path = path.join("a").join("b");
    match new_path.to_str() {
        None => panic!("new Path is not a valid UTF-8 sequence"),
        Some(s) => println!("new path is {}", s),
    }
}
